V. I. Lutskii

Hydroxystilbenes of the inner bark of Pinus sibirica

SummaryIn addition to pinostilbene and resveratrol, two new stilbene glycosides have been isolated from the phloem ofPinus sibirica R. Mayr, and their structures have been established as 3,4′-dihydroxy-5-methoxy-stilbene 4′-β-D-glycopyranoside (pinostilbenoside) and 3,4′,5-trihydroxystilbene 4′-β-D-glycopyranoside (resveratroloside).

Phenolic acids of the phloem of Abies nephrolepis, Pinus sibirica, and P. sylvestris

Evapora ted methanol ic ex t r ac t s of Khingan fir, Siberian pine, and Scotch pine were sepa ra t ed by t r e a t ment with diethyl e ther into two fract ions . F rom the e the r so lub le solution by a method desc r ibed p rev ious ly [1] we isolated the phenolic acid f ract ions: p-hydroxybenzoic , vanil l ic, protocatechuic , p c o u m a r i c , and ferul ic acids . F r o m the e the r inso lub le ex t rac t by p r epa ra t i ve ch romatography on polyamide we obtained a f rac t ion of glycosidated phenolic acids .

Hydroxystilbenes from the bark of Pinus sibirica

SummaryFrom the bark ofPinus sibirica R. Mayr have been isolated 3,4′,5-trihydroxystilbene (resveratrol), not previously known for the genusPinus, and a new stilbene — pinostilbene — for which the structure 3,4′-dihydroxy-5-methoxystilbene has been established.

Phenolic acids of the bark of Pinus silvestris, P. sibirica, and P. abies nephrolepis

Acetone extracts of the barks of Pinus st lvestr is L. (Scots pine) and P. abies nephrolepis Maxim (whitebark pine) were treated with petroleum ether to eliminate waxy substances and then with dtethyl e ther in o rde r to extract the polar phenolic components. The phenolic acids were obtained from the ethereal fractions by extraction with saturated sodium bicarbonate solution. The phenolic acids f r o m an extract of the bark of P. sibirica R. Mayr (Siberian pine) were isolated by a method described previously [1].

Phenolic components of the bark ofPinus sibirica andP. silvestris

Crysta l l ine substances were isolated by prepara t ive chromatography on polyamide sorbent and were charac te r ized by their UV and IR spect ra and melt ing points. In addition, the compounds obtained were identified in the presence of authentic samples of phenols by th inlayer chromatography on polyamide under the conditions of both par t i t ion (methanol -wate r system) and adsorption (chloroform-methanol) p rocesses [2].

Esters of phenolic acids of the bark ofPicea ajanensis, P. koraiensis, andP. obovata

There is information in the literature on the isolation from the bark of coniferous plants of a phenolic wax consisting of esters of phenolic acids and n-aliphatic alcohols. Thus, from the bark of some species of spruce [la], fir [2], broad-leaved trees [3, 4], and pines [ib, 2, 5] esters of ferulic acid have been isolated, and from the bark of the Norway spruce esters of p-coumaric acid, in addition [la].

PMR spectra of natural stilbene compounds

Summary1. The PMR spectra of 13 natural stilbenes have been studied.2. The dominating role of π-electron interaction of the fragments of the stilbene molecule in the screening of the aromatic and olefinic protons has been shown. A series of increments presenting interest for determining the structure of stilbene compounds is proposed.3. It has been established that the nature and nature and number of the substituents in the aglycone part of the molecule have no influence on the screening of the anomeric proton of glycosidated stilbenes, but it does depend on the position of attachment of the carbohydrate fragment.